Fatigue properties of a structural rotor blade adhesive under axial and torsional loading

authored by

Michael Kuhn, Nikolas Manousides, Alexandros Antoniou, Claudio Balzani

Abstract

Axial and torsional fatigue tests at different stress ratios were performed on a structural adhesive designed for wind turbine rotor blades. By employing previously optimized specimens, fatigue properties were recorded without influences of manufacturing-induced defects such as pores. The Stüssi S–N model was an excellent fit to the data and was combined with a Haibach extension line to account for uncertainties in the gigacycle fatigue regime. A comparison of the results with hand-mixed specimens revealed significant and load level-dependent differences, indicating that manufacturing safety factors should be applied to the slope of the S–N curve. The experiments were accompanied by stiffness degradation measurements, which enabled an analysis of Young's and shear modulus degradation interactions. The degradation was modeled using power law fits, which incorporated load level-dependent fitting parameters to allow for a full description of the stiffness reduction and a prediction of the residual fatigue life of run-out specimens.

Organisation(s)

Institute of Wind Energy Systems

External Organisation(s)

Fraunhofer Institute for Wind Energy Systems (IWES)

Type

Article

Journal

Fatigue and Fracture of Engineering Materials and Structures

Volume

46

Pages

1121-1139

No. of pages

19

ISSN

8756-758X

Publication date

08.02.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Materials Science, Mechanics of Materials, Mechanical Engineering

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1111/ffe.13925 (Access: Open)